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1.
PLoS One ; 18(12): e0295963, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38157385

RESUMO

Depending on the trading modes, the effect of Outward Foreign Direct Investment (OFDI) on the manufacturing industry's position within the global value chain (GVC) may differ considerably. This paper examines the GVC position of China's manufacturing industry from 2003 to 2018, specifically focusing on the general trade and processing trade. Drawing upon this premise, this paper analyzes the effect and mechanism by which OFDI influences the GVC position of China's manufacturing industry. The result demonstrates that: (1) China's processing trade manufacturing industry has a much lower GVC position than general trade manufacturing industry. The GVC position of China's general trade manufacturing industry rose from 2.76 to 2.90 from 2003 to 2018, while processing trade manufacturing industry remained around 1.93. (2) OFDI boosts the GVC position of general trade manufacturing industry through facilitating reverse technology spillover, inducing industry structure upgrading, and enabling export scale expansion. (3) OFDI hinders the GVC position growth of processing trade manufacturing industry. The research findings offer theoretical backing for China to develop OFDI strategies that are tailored to different trading modes within the new framework of dual circulation. These strategies aim to facilitate the transformation and advancement of the manufacturing industry, as well as the growth of the GVC position.


Assuntos
Indústrias , Indústria Manufatureira , Comércio , Tecnologia , China , Desenvolvimento Econômico
2.
PLoS One ; 18(11): e0293962, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37939047

RESUMO

China's economy has made remarkable achievements in the past 40 years. However, the economic development is accompanied by serious environmental pollution. Chinese government has promulgated many policies to reduce environment pollution. However, it is doubtable whether the increased uncertainty in environmental policies inhibits enterprise development. Therefore in this study we use Mathematical Derivation, Stepwise Regression Method and Regulated Effect to investigate the impact of environmental policy uncertainty on enterprise productivity. The results show that (1) environmental policy uncertainty significantly inhibits the improvement of enterprise productivity. (2) environmental policy uncertainty inhibits enterprise productivity by enterprise innovation, human capital and foreign direct investment; (3) environmental policy uncertainty has heterogeneous impact on enterprise productivity. According to this study we also provide some beneficial environmental policy suggestions for the Chinese government. Such as the government should build a stable economic environment, maintain the sustainability of local environmental regulation policies and formulate more detailed measures to adapt different types of enterprises.


Assuntos
Política Ambiental , China , Desenvolvimento Econômico , Poluição Ambiental , Incerteza
3.
PLoS One ; 18(7): e0288277, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37459315

RESUMO

In nature and human societies, the effects of homogeneous and heterogeneous characteristics on the evolution of collective behaviors are quite different from each other. By incorporating pair pattern strategies and reference point strategies into an agent-based model, we have investigated the effects of homogeneous and heterogeneous investment strategies and reference points on price movement. In the market flooded with the investors with homogeneous investment strategies or homogeneous reference points, large price fluctuations occur. In the market flooded with the investors with heterogeneous investment strategies or heterogeneous reference points, moderate price fluctuations occur. The coexistence of different kinds of investment strategies can not only refrain from the occurrence of large price fluctuations but also the occurrence of no-trading states. The present model reveals that the coexistence of heterogeneous populations, whether they are the individuals with heterogeneous investment strategies or heterogeneous reference points of stock prices, is an important factor for the stability of the stock market.


Assuntos
Inundações , Investimentos em Saúde , Humanos
4.
Front Microbiol ; 14: 1093745, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36910195

RESUMO

Introduction: Mycobacterium tuberculosis (MTB) identification and drug resistance diagnosis are very important for treatment of drug-resistant tuberculosis (DR-TB). Therefore, high throughput, accurate and low-cost molecular detection techniques are urgently needed. This study aimed to evaluate the clinical application value of MassARRAY in tuberculosis diagnosis and drug resistance screening. Methods: The limit of detection (LOD) and clinical application value of MassARRAY were evaluated using reference strains and clinical isolates. MTB in bronchoalveolar lavage fluid (BALF) and sputum samples were detected using MassARRAY, quantitative real-time polymerase chain reaction (qPCR) and MGIT960 liquid culture (culture). Using culture as the standard, the efficacy of MassARRAY and qPCR for the detection of TB was analyzed. Mutation of drug resistance genes in MTB clinical isolates was tested using MassARRAY, high-resolution melting curve (HRM), and Sanger sequencing. Using sequencing as the standard, the efficacy of MassARRAY, and HRM for the detection of each drug resistance site of MTB was analyzed. Simultaneously, the mutation of drug resistance genes by the MassARRAY method was compared with the results of drug susceptibility testing (DST), and the genotype-phenotype relationship was analyzed. The ability of MassARRAY to discriminate mixed infections was detected using mixtures of standard strains (M. tuberculosis H37Rv) and drug-resistant clinical isolates and mixtures of wild-type and mutant plasmids. Results: In MassARRAY, 20 related gene mutations could be detected by two PCR systems. All genes could be accurately detected when the bacterial load was 104 CFU/mL. When the load of wild-type and drug-resistant MTB mixture was 105 CFU/mL (respectively reached 104 CFU/mL), variants and wild-type genes could be detected simultaneously. The sensitivity of MassARRAY (96.9%) for identification was higher than that of qPCR (87.5%) (p < 0.001). The sensitivity and specificity of MassARRAY for all drug resistance gene mutations were 100.0%, with higher accuracy and consistency than HRM (sensitivity = 89.3% and specificity = 96.9%, p = 0.001). Analyzing the relationship between MassARRAY genotype and DST phenotype, the accuracy of katG_315, rpoB_531, rpsL_43, rpsL_88, and rrs_513 sites was 100.0%, and embB_306 and rpoB_526 were inconsistent with the DST results when the base changes were different. Discussion: MassARRAY can obtain base mutation information and identify heteroresistance infections simultaneously when the mutant proportion was at least 5-25%. It has good application prospects in the diagnosis of DR-TB with high throughput, accurate and low-cost.

5.
Arch Biochem Biophys ; 739: 109568, 2023 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-36914110

RESUMO

Deposition of calcium oxalate (CaOx) crystals and oxidative stress-induced injury of renal tubular epithelial cell are the primary pathogenic factors of nephrolithiasis. In this study we investigated the beneficial effects of metformin hydrochloride (MH) against nephrolithiasis and explored the underlying molecular mechanism. Our results demonstrated that MH inhibited the formation of CaOx crystals and promoted the transformation of thermodynamically stable CaOx monohydrate (COM) to more unstable CaOx dihydrate (COD). MH treatment effectively ameliorated oxalate-induced oxidative injury and mitochondrial damage in renal tubular cells and reduced CaOx crystal deposition in rat kidneys. MH also attenuated oxidative stress by lowering MDA level and enhancing SOD activity in HK-2 and NRK-52E cells and in a rat model of nephrolithiasis. In both HK-2 and NRK-52E cells, COM exposure significantlylowered the expressions of HO-1 and Nrf2, which was rescued by MH treatment even in the presence of Nrf2 and HO-1 inhibitors. In rats with nephrolithiasis, MH treatment significantly rescued the down-regulation of the mRNA and protein expression of Nrf2 and HO-1 in the kidneys. These results demonstrate that MH can alleviate CaOx crystal deposition and kidney tissue injury in rats with nephrolithiasis by suppressing oxidative stress and activating the Nrf2/HO-1 signaling pathway, suggesting the potential value of MH in the treatment of nephrolithiasis.


Assuntos
Cálculos Renais , Metformina , Ratos , Animais , Oxalato de Cálcio/química , Oxalato de Cálcio/metabolismo , Oxalato de Cálcio/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Cristalização , Metformina/farmacologia , Metformina/uso terapêutico , Metformina/metabolismo , Rim/patologia , Cálculos Renais/tratamento farmacológico , Cálculos Renais/metabolismo , Cálculos Renais/patologia , Transdução de Sinais
6.
Front Public Health ; 10: 1050971, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36504993

RESUMO

Introduction: Air pollution not only harms people's health, but also impedes urban economic development. This study aims to analyze how air quality improvement affects enterprise productivity. And then from regional and time heterogeneities' aspects to investigate if the air quality improvement increase enterprise productivity. Methods: The data were obtained from China Industrial Enterprise Database and China Patent Database,and this study used Spatial Durbin Model to analyze how air quality improvement affects enterprise productivity. Results: The results show that: (1) air quality improvement and its spatial spillover effect can significantly increase enterprise productivity in adjacent areas. (2) After 2010, the government implemented more stringent measures to prevent and control air pollution, which made the air quality improvement promote enterprise productivity increase more obviously. The air quality improvement in eastern and central regions was less obvious than in western regions. (3) Air quality improvement can increase enterprise productivity by improving enterprise innovation quality, ensuring the health of urban residents, and increasing the stock of urban human capital. Conclusion: Air quality improvement and its spatial spillover effect can significantly increase enterprise productivity in adjacent areas. So this study puts forward some policy enlightenment, such as establishing an air pollution detection system, using an intelligent network supervision platform, and implementing a coordinated defense and governance system.


Assuntos
Poluição do Ar , Melhoria de Qualidade , Humanos , Cidades , Desenvolvimento Econômico , Indústrias
7.
Front Psychol ; 13: 979027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36312131

RESUMO

This paper focuses on the impact of the "Digital Economy" on rural entrepreneurship. Unlike previous literature, the perspective of this paper focuses on a specific industry-tourism-and identifies a new mediating mechanism by which the "Digital Economy" affects rural tourism entrepreneurship-the promotion of innovation. The paper further clarifies the fact that the "Rural Digital Economy Index," which is a dimension of the Digital Economy Indicator System, is the key to the mechanism of action. Theoretically, first, through a literature review, this paper provides a rationale for the "Digital Economy" to promote innovation behavior by reducing the cost of innovation. Second, using a product matching model, this paper argues that a rural tourism market characterized by innovation can stimulate more entrepreneurship. Empirically, using a sample of 150 counties in the Yangtze River Delta region of China, this paper argues that the higher the digitalization index of a county's rural economy, the more national model villages and towns this county has (all of which include product innovation in the selection criteria) and more tourism entrepreneurial activities. Econometric methods such as endogeneity, spatial econometric regression, and sensitivity analysis proved the findings robust. Our recommendation is that the Chinese government could focus on improving the innovation environment for rural residents in the future, so that entrepreneurial activities will be spontaneously stimulated by market mechanisms.

8.
Comput Math Methods Med ; 2022: 8026689, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35664637

RESUMO

Objectives: Noninvasive left ventricular pressure-strain loop (PSL) is a new method for quantitative evaluation of myocardial work, which is developed on the basis of speckle tracking echocardiography. It is necessary to fit the noninvasive left ventricular pressure and the strain by speckle tracking echocardiography to construct a pressure-strain loop. Compared with traditional left ventricular ejection fraction (LVEF) and global longitudinal strain (GLS), it has potential application value and is a useful supplement for clinical evaluation of left ventricular systolic function. We perform this study to evaluate the changes of myocardial function in patients with non-ST-segment elevation acute coronary syndrome (NSTE-ACS) before and after percutaneous coronary intervention (PCI) with noninvasive left ventricular pressure-strain loop (PSL). Methods: 33 NSTE-ACS patients admitted to the Department of Cardiovascular Medicine of the Affiliated Lianyungang Hospital of Xuzhou Medical University who successfully underwent early PCI were included as the PCI group. At the same time, 30 healthy patients matched in age and sex were selected as the control group. All patients received routine echocardiography. The parameters such as GWI, GCW, GWW, and GWE were obtained by EchoPAC 203 software. The differences in the general clinical data and echocardiographic parameters between the two groups, including controls and patients 1 day before surgery and 1 month after surgery, were compared. Results: Compared with the control group, GWI, GCW, and GWI in the PCI group were decreased 1 day before surgery and 1 month after surgery, while GWW was increased, with statistical significance (P < 0.05). In the PCI group, compared with 1 day before surgery, GWI and GCW were all increased 1 month after surgery (P < 0.05), and GWW and GWE were not significantly different between the two groups (P > 0.05). Conclusion: The noninvasive left ventricular PSL technology can early and accurately evaluate the myocardial function impairment in NSTE-ACS patients and the recovery of myocardial function after PCI, providing a new noninvasive method for clinical postoperative myocardial function evaluation.


Assuntos
Síndrome Coronariana Aguda , Intervenção Coronária Percutânea , Síndrome Coronariana Aguda/diagnóstico por imagem , Síndrome Coronariana Aguda/cirurgia , Ventrículos do Coração/diagnóstico por imagem , Humanos , Intervenção Coronária Percutânea/métodos , Volume Sistólico , Tecnologia , Função Ventricular Esquerda/fisiologia
9.
Sci Rep ; 10(1): 3435, 2020 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-32103052

RESUMO

The popular medicinal mushroom Ganoderma lucidum (Fr.) Karst. [Ling Zhi] has been widely used for the general promotion of health and longevity in Asian countries. Continuous cultivation may affect soil microbe and soil properties. However, the effect of G. lucidum cultivation on related wood segments, soil and tree roots microbial communities and soil properties is remain unknown. In our study, the microbial communities of soils, wood segments, and tree roots before and after G. lucidum cultivation were investigated by Illumina Miseq sequencing of both ITS and 16S rDNA, and taxonomic composition of eukaryotic and prokaryotic microorganisms were observed. Indices of microbial richness, diversity and evenness significantly differed between before and after G. lucidum cultivation. Each of the investigated sampling type harbored a distinctive microbial community and differed remarkably before and after G. lucidum cultivation. Ascomycota and Basidiomycota (fungi), Proteobacteria and Actinobacteria (bacteria) showed significant differences after Ling Zhi cultivation. The soil property values also changed after cultivation. The redundancy analysis (RDA) showed that both the fungal and bacterial community structure significantly correlated with soil humus, pH, nitrogen, carbon and trace elements (Fe, Zn, Mn, Cu) contents. The results indicated that G. lucidum cultivation may have significant differed the associated microbial community structures and soil properties. The study will provide useful information for G. lucidum cultivation and under-forest economic development.


Assuntos
Reishi/crescimento & desenvolvimento , Microbiologia do Solo , Solo/química , Madeira/microbiologia , Actinobacteria/genética , Actinobacteria/isolamento & purificação , Ascomicetos/genética , Ascomicetos/isolamento & purificação , Basidiomycota/genética , Basidiomycota/isolamento & purificação , Microbiota , Raízes de Plantas/microbiologia , Proteobactérias/genética , Proteobactérias/isolamento & purificação , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , RNA Ribossômico 16S/metabolismo , Análise de Sequência de DNA
10.
PLoS One ; 12(1): e0169299, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28129333

RESUMO

The problem of portfolio optimization is one of the most important issues in asset management. We here propose a new dynamic portfolio strategy based on the time-varying structures of MST networks in Chinese stock markets, where the market condition is further considered when using the optimal portfolios for investment. A portfolio strategy comprises two stages: First, select the portfolios by choosing central and peripheral stocks in the selection horizon using five topological parameters, namely degree, betweenness centrality, distance on degree criterion, distance on correlation criterion and distance on distance criterion. Second, use the portfolios for investment in the investment horizon. The optimal portfolio is chosen by comparing central and peripheral portfolios under different combinations of market conditions in the selection and investment horizons. Market conditions in our paper are identified by the ratios of the number of trading days with rising index to the total number of trading days, or the sum of the amplitudes of the trading days with rising index to the sum of the amplitudes of the total trading days. We find that central portfolios outperform peripheral portfolios when the market is under a drawup condition, or when the market is stable or drawup in the selection horizon and is under a stable condition in the investment horizon. We also find that peripheral portfolios gain more than central portfolios when the market is stable in the selection horizon and is drawdown in the investment horizon. Empirical tests are carried out based on the optimal portfolio strategy. Among all possible optimal portfolio strategies based on different parameters to select portfolios and different criteria to identify market conditions, 65% of our optimal portfolio strategies outperform the random strategy for the Shanghai A-Share market while the proportion is 70% for the Shenzhen A-Share market.


Assuntos
Análise por Conglomerados , Declarações Financeiras/economia , Investimentos em Saúde/economia , Modelos Econômicos , China , Humanos , Investimentos em Saúde/estatística & dados numéricos
11.
Ecol Evol ; 7(24): 10575-10581, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-29299239

RESUMO

In competition-dominated communities, traits promoting resource conservation and competitive ability are expected to have an important influence on species relative abundance (SRA). Yet, few studies have tested the trait-abundance relations in the line of species trade-off in resource conservation versus acquisition, indicating by multiple traits coordination. We measured SRA and key functional traits involving leaf economic spectrum (SLA, specific leaf area; LDMC, leaf dry matter content; LCC, leaf carbon concentration; LNC, leaf nitrogen concentration; LPC, leaf phosphorus concentration; Hs, mature height) for ten common species in all plots subjected to addition of nitrogen fertilizer (N), phosphorus fertilizer (P), or both of them (NP) in a Tibetan alpine meadow. We test whether SRA is positively related with traits promoting plant resource conservation, while negatively correlated with traits promoting plant growth and resource acquisition. We found that species were primarily differentiated along a trade-off axis involving traits promoting nutrient acquisition and fast growth (e.g., LPC and SLA) versus traits promoting resource conservation and competition ability (e.g., large LDMC). We further found that SRA was positively correlated with plant height, LDMC, and LCC, but negatively associated with SLA and leaf nutrient concentration irrespective of fertilization. A stronger positive height-SRA was found in NP-fertilized plots than in other plots, while negative correlations between SRA and SLA and LPC were found in N or P fertilized plots. The results indicate that species trade-off in nutrient acquisition and resource conservation was a key driver of SRA in competition-dominated communities following fertilization, with the linkage between SRA and traits depending on plant competition for specific soil nutrient and/or light availability. The results highlight the importance of competitive exclusion in plant community assembly following fertilization and suggest that abundant species in local communities become dominated at expense of growth while infrequent species hold an advantage in fast growth and dispersals to neighbor meta-communities.

12.
Dalton Trans ; 44(44): 19370-82, 2015 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-26501793

RESUMO

Three new metal organic frameworks (MOFs) with chemical formulae [(CH3)2NH2] [Sm3(L1)2(HCOO)2(DMF)2(H2O)]·2DMF·18H2O (1), [Cu2(L2)(H2O)2]·2.22DMA (2) and [Zn2(L1)(DMA)]·1.75DMA were synthesized and structurally characterized. 1 and 2 show a classical NbO-like topology and have two types of interconnected cages. 3 exhibits an uncommon zzz topology and has two types of interconnected cages. These MOFs can adsorb large amounts of the drug 5-fluorouracil (5-FU) and release it in a progressive way. 5-FU was incorporated into desolvated 1, 2 and 3 with loadings of 0.40, 0.42, and 0.45 g g(-1), respectively. The drug release rates were 72%, 96% and 79% of the drug after 96 hours in 1, 120 hours in 2 and 96 hours in 3, respectively. Grand Canonical Monte Carlo (GCMC) simulations were performed to investigate the molecular interactions during 5-FU adsorption to the three novel materials. The GCMC simulations reproduced the experimental trend with respect to the drug loading capacity of each material. They also provided a structural description of drug packing within the frameworks, helping to explain the load capacity and controlled release characteristics of the materials. 5-FU binding preferences to 1, 2 and 3 reflect the diversity in pore types, chemistry and sizes. The calculated drug load is more related to the molecular properties of accessible volume Vacc than to the pore size.


Assuntos
Sistemas de Liberação de Medicamentos , Nanopartículas/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Adsorção , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/química , Simulação por Computador , Cristalografia por Raios X , Fluoruracila/administração & dosagem , Fluoruracila/química , Cromatografia Gasosa-Espectrometria de Massas , Modelos Moleculares , Método de Monte Carlo
13.
PLoS One ; 9(5): e97711, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24867071

RESUMO

The analysis of cross-correlations is extensively applied for the understanding of interconnections in stock markets and the portfolio risk estimation. Current studies of correlations in Chinese market mainly focus on the static correlations between return series, and this calls for an urgent need to investigate their dynamic correlations. Our study aims to reveal the dynamic evolution of cross-correlations in the Chinese stock market, and offer an exact interpretation for the evolution behavior. The correlation matrices constructed from the return series of 367 A-share stocks traded on the Shanghai Stock Exchange from January 4, 1999 to December 30, 2011 are calculated over a moving window with a size of 400 days. The evolutions of the statistical properties of the correlation coefficients, eigenvalues, and eigenvectors of the correlation matrices are carefully analyzed. We find that the stock correlations are significantly increased in the periods of two market crashes in 2001 and 2008, during which only five eigenvalues significantly deviate from the random correlation matrix, and the systemic risk is higher in these volatile periods than calm periods. By investigating the significant contributors of the deviating eigenvectors in different time periods, we observe a dynamic evolution behavior in business sectors such as IT, electronics, and real estate, which lead the rise (drop) before (after) the crashes. Our results provide new perspectives for the understanding of the dynamic evolution of cross-correlations in the Chines stock markets, and the result of risk estimation is valuable for the application of risk management.


Assuntos
Comércio/economia , Investimentos em Saúde/economia , Marketing/economia , Modelos Econômicos , Algoritmos , Comércio/estatística & dados numéricos , Comércio/tendências , Humanos , Investimentos em Saúde/estatística & dados numéricos , Investimentos em Saúde/tendências , Marketing/estatística & dados numéricos , Marketing/tendências , Gestão de Riscos , Fatores de Tempo
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